As a technique of interest related to the present disclosure, for example, there has been known a technique described in Japanese patent 4184394. FIG. 9 and FIG. 10 are drawings cited from Japanese patent 4184394, and correspond to FIG. 2 and FIG. 4 in Japanese patent 4184394, respectively. FIG. 9 and FIG. 10 show one flange portion 1 which forms a portion of a core provided to a coil component, a metal terminal 2 disposed on the flange portion 1, and an end portion of a wire 3 connected to the metal terminal 2.
As shown in FIG. 9 and FIG. 10, the wire 3 includes: a conductive wire portion 4 made of a conductor; and an insulating resin coating 5 which covers a peripheral surface of the conductive wire portion 4. The metal terminal 2 includes: a base portion 7 disposed on an outer end surface 6 side of the flange portion 1; and a receiving portion 9 extending from the base portion 7 by way of a bent portion 8 and receiving the end portion of the wire 3. The metal terminal 2 further includes: a welding portion 11 extending from the receiving portion 9 by way of a first folding portion 10 and welded to the conductive wire portion 4 of the wire 3; and a holding portion 13 extending from the receiving portion 9 by way of a second folding portion 12 and positioning the wire 3 by holding the wire 3.
With respect to the above-mentioned welding portion 11, a state of the welding portion 11 before a welding step is performed is shown in FIG. 9, and a state of the welding portion 11 after the welding step is performed is shown in FIG. 10. In FIG. 10, a melted ball 14 formed by welding is shown. The melted ball 14 is formed in such a manner that molten metal formed by welding is formed into a ball shape by surface tension, and the molten metal is solidified by being cooled while keeping a ball shape.
The detail of a step of connecting the wire 3 to the metal terminal 2 is described hereinafter. In a stage before such a connecting step is performed, in the metal terminal 2, the welding portion 11 and the holding portion 13 are in a state where the welding portion 11 and the holding portion 13 are opened with respect to the receiving portion 9 so that neither the welding portion 11 nor the holding portion 13 face the receiving portion 9. FIG. 9 shows a state where the welding portion 11 is opened with respect to the receiving portion 9 although the holding portion 13 faces the receiving portion 9.
Firstly, the wire 3 is placed on the receiving portion 9 of the metal terminal 2. To fix this state temporarily, the holding portion 13 is folded with respect to the receiving portion 9 by way of the second folding portion 12 such that the wire 3 is sandwiched between the receiving portion 9 and the holding portion 13.
Next, as shown in FIG. 9, a portion of the insulating resin coating 5 of the wire 3 disposed on a more distal end side than the holding portion 13 is removed. For example, a laser beam is irradiated to the insulating resin coating 5 for removing the insulating resin coating 5. As can be clearly understood from FIG. 9, a portion of the insulating resin coating 5 which is in contact with the receiving portion 9 is left without being removed.
Next, the welding portion 11 is folded with respect to the receiving portion 9 by way of the first folding portion 10 thus bringing about a state where the wire 3 is sandwiched between the welding portion 11 and the receiving portion 9.
Then, the conductive wire portion 4 of the wire 3 and the welding portion 11 are welded to each other. To be more specific, laser welding is applied. A laser beam is irradiated to the welding portion 11 so that the conductive wire portion 4 of the wire 3 and the welding portion 11 are melted to each other. A liquefied molten portion is formed into a ball shape by surface tension. Thereafter, the molten portion is solidified while keeping a ball shape so that the melt ball 14 is formed.